Distributor rotor



Dec. 30, 1941. DECKER 2,267,818

' DISTRIBUTOR ROTOR Filed May 23, 1940 INVENTOR HUGH L.DEC'KEB BY 5: I 7 ATTORNEYS Patented Dec. 30, 1941 UNITED STATES PATENT OFFICE DISTRIBUTOR ROTOR Hugh L. Decker, Bay City, Mich.

Application May 23, 1940, Serial No. 336,793

2 Claims.

This invention relates to the method of attaching a rotating device to a non-circular driving means, more particularly to the method of attaching the rotor to the central rotating shaft of an ignition distributor in an automotive device.

Heretofore rotors have been attached to the central shaft in distributors by using cooperating male and female members adapted to form a snug fit therebetween wherein the male driving member, usually formed of metal, has been provided with a non-circular portion to be embraced by the female member consisting of a collar of similar non-circular contour formed in the insulating substance of which the complete rotor is formed. Rotors in general used for this purpose have been made of phenol condensate products, such as Bakelite or the like, and it has been found that these substances are relatively unstable over a long period of time and tend to grow, so that the snug embracing fit between the part-s is lost and the parts become movable relative to each other. Due to the growth of the insulating material, a wobbling of the rotor is apt to occur which is extremely undesirable, in that it may change the timing relations of the automotive engine, or it may change the gap relations between the rotor electrodes and the fixed electrodes to unequally distribute the electrical energy to the spark plugs. The unequal distribution of energy to the various spark plugs is also undesirable. The growth of the insulating material may also cause the distributor to become useless due to a dragging of the rotating parts on the stationary parts.

The present invention is designed to overcome these difficulties by providing a method of attaching the rotor to the non-circular driving means which will compensate for the growth of the unstable insulating substance, so that even if a considerable amount of growth isoccasioned by the aging of the insulation material of the rotor, the operating conditions in the ignition system remain substantially unchanged. In order to do this, a resilient spring member is positioned in a manner to be described in detail hereinafter between the insulating rotor and the driving means to place a lateral thrust between the two cooperating members, so that any change in dimension of the insulating substance is substantially compensated for so as to prevent interferences with the critical longitudinal dimensions of the rotor with reference to its driving means.

It is, therefore, a principal object of this invention to provide a means for attaching a driven means fabricated of relatively unstable insulating substance to a non-circular driving shaft in a manner to prevent any change of operating characteristic or critical dimension of the rotor even though the insulating substance of the rotor is subject to growth or change of dimension durmg aging.

It is a further object of this invention to provide a means for fastening a rotor of a distributing head of an automotive ignition system to a non-circular driving means thereof which will prevent wobbling of the rotor on the driving means when the insulating material of which the rotor is made is subjected to growth, so as to cause a slight change of dimension.

Other objects and advantages of this invention relating to the arrangement, operation and function of the related elements of the structure, to various details of construction, to combinations of parts and to economies of manufacture, will be apparent to those skilled in the art upon consideration of the following description and appended claims, reference being had to the accompanying drawing forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

Figure l is an elevational view, partly in section, showing the details of construction of the usual type of distributor head to which the invention has been applied.

Figure 2 is an elevational view, partly in section, showing the method of attaching the rotor to the non-circular driving means.

Figure 3 is an elevational View of one of the elements.

Figure 4 is a plan view of the same.

Figure 5 is a bottom plan view of the same.

Figure 6 is a bottom plan view taken along the line 66 of Figure 2.

Referring to Figure 1 of the drawing, a cupshaped container ID of a conventional distributor is shown which is provided with an insulating cap ll having molded therein metallic inserts l2 which project into the interior of the cap to provide electrode members 13, a series of which are peripherally mounted as shown. Adjacent the central position, electrode insert [2a is provided in whose hollow lower end brush member I4 is positioned, being urged downwardly by a spring member 15 to bear against a revolving electrode l6 mounted on a rotating block I! of insulating material by means of rivet insert Mia. The outer end of the electrode member I6 is adapted to rotate with the brush member 14 as a center, so as to cooperate with the peripheral electrode members I3 through a short spark gap whereby high tension electrical energy which enters the distributor through the insert l2a may be distributed consecutively in timed relation to the electrode members I3 by the rotation of the block H.

The rotor block I1 is carefully balanced for weight distribution and is positioned on the end Ila having a bore 22 generally conforming to the non-circular contour of the stud 2|, the boss being adapted to embrace the stud as is clearly shown in Figure 2. Adjacent the non-circular side 2la of the stud, the bore 22 is provided with a pair of flattened portions 22a slightly spaced from the non-circular side 2 la. A curved spring member (Figure 3) 23 is adapted to be positioned in the space between the non-circular side Zla of the stud and the flattened portions 22a of the bore 22, the spring having adjacent its upper end a small integral tongue 2d which cooperates with the groove 22?) centrally located between the flattened portions 22a. A solemember 25 is also integrally attached to the upper end of the spring and extends substantially at right angles to the spring, the sole member 25 being substantially circular in contour, so as to fit the bottom of the bore 22. When the rotor IT is in position on the stud 2!, the sole member 25 will be positioned between the bottom of the bore 22 and the top of the stud 2K, to hold the spring member 23 firmly in position and to give it an anchorage to apply a lateral thrust to the block I! with reference to the rotating electrode it as is clearly shown in Figure 2. The tongue 24 cooperates with the vertical groove 22b to provide a guiding means for the spring element and also to further prevent relative rotation between the rotor ll and the stud 2 l. Inasmuch as there is an angular relation between the tongue 24 and the bottom of the groove 222), a locking action occurs therebetween to keep the sole member 25 in position upon the removal of the whole from the stud, the end of the tongue biting the bottom of the groove.

Referring to Figure 6, it is clear that the spring 23 thrusts the rotor il laterally with reference to the stud 2 i, so as to substantially prevent any longitudinal change of dimensions during conditions in which the dimensions of the stud Ila." is changed while growing under an aging process which is well known with reference to phenol condensate products such as Bakelite. The fact that the spring 23 applies a lateral thrust to the rotor block ll, assuming that the longitudinal dimension is parallel with the axis of the rotating element Hi, it is clear that even though there be considerable growth on the part of the boss ll'a, this change in dimension will be substantially compensated and equalized by the lateral thrust to prevent any substantial change in dimension along the longitudinal axis, which change would be very undesirable inasmuch as it is immediately reflected in the dimension of the spark gap between the end of the rotating electrode l6 and the stationary electrodes 83 positioned peripherally of the insulating cap H. The growth of the rotating bio-ck, therefore, does not change this longitudinal dimension substantially, and any change that occurs is equalized to vary the spark gap equally between all the electrodes l3 and the rotating electrode I6.

In a similar manner, the action of the spring 23 will compensate for any looseness of fit between the bore 22 and the stud 2|, so as to prevent wobbling. Inasmuch as the sole member 25 is positioned between the bottom of the bore 22 and the top of the stud 2! and cooperates with the spring 23 to anchor the same, together they will substantially prevent any displacement between the elements, so that the electrode It cannot be displaced from the plane of the fixed electrodes 13.

It is to be understood that the above detailed description of the present invention is intended to disclose an embodiment thereof to those skilled in the art, but that the invention is not to be construed as limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawing, since the invention is capable of being practiced and carried out in various ways Without departing from the spirit of the invention. The language used in the specification relating to the operation and function of the elements of the invention is employed for purposes of description and not of limitation, and it is not intended to limit the scope of the following claims beyond the requirements of the prior art.

What isclaimed:

1. In a device of the class described, a noncircular driving member, a supporting member for the driving member, a relatively stationary electrode on the supporting member, a cupshaped drivenmember embracing the end of the non-circular driving member and adapted to rotate therewith in a plane transverse of the driving member, an electrode mounted on the driven member adapted to cooperate with the stationary electrode at predetermined times during the rotation of the driven member, resilient means acting transversely of radial axis of the electrode on the driven member to maintain a snug cooperative relation between the driving member and the cup-shaped driven member, and holding means to maintain the resilient means in position and to prevent relative rotation between the resilient means and the cup-shaped driven member.

2. In a device of the class described, a noncircular driving means, a cup-shaped driven member made of relatively unstable insulating substance cooperating with the driving means by embracing the end thereof, a relatively stationary supporting means for the driving means, an electrode insulatably mounted on the supporting means, a movable electrode mounted on the driven member to cooperate with the electrode mounted on the supporting means by being spaced therefrom at a predetermined distance at predetermined times during the rotation of the driven member, resilient means acting transversely of the radial axis of the movable electrode tending to separate the driving means from the driven member to compensate for growth or change of dimension of the relaiively unstable insulating substance of the driven member during the aging thereof to maintain the predetermined distance between the electrodes substantially constant, and holding means to maintain the position of the resilient means and to prevent relative rotation between the driving means and the driven member.

HUGH L. DECKER. 

